On Fri, Jun 18, 2010 at 12:58 PM, Prerna Saxena
<prerna@xxxxxxxxxxxxxxxxxx> wrote:
> Hi Stefan, Jan,
> Thanks for taking a look.
>
> On 06/17/2010 08:38 PM, Stefan Hajnoczi wrote:
>>
>> On Wed, Jun 16, 2010 at 06:12:06PM +0530, Prerna Saxena wrote:
>>>
>>> diff --git a/simpletrace.c b/simpletrace.c
>>> index 2fec4d3..239ae3f 100644
>>> --- a/simpletrace.c
>>> +++ b/simpletrace.c
>>> @@ -62,3 +62,16 @@ void trace4(TraceEvent event, unsigned long x1,
>>> unsigned long x2, unsigned long
>>> void trace5(TraceEvent event, unsigned long x1, unsigned long x2,
>>> unsigned long x3, unsigned long x4, unsigned long x5) {
>>> trace(event, x1, x2, x3, x4, x5);
>>> }
>>> +
>>> +void do_info_trace(Monitor *mon)
>>> +{
>>> + unsigned int i, max_idx;
>>> +
>>> + max_idx = trace_idx ? trace_idx : TRACE_BUF_LEN;
>>
>> trace_idx is always in the range [0, TRACE_BUF_LEN). There is no need
>> to perform this test.
>
> I only display the logged contents in the trace buffer (till trace_idx) ,
> and not the entire trace buffer. Only when the index is full that the entire
> buffer is displayed.
Thanks for explaining, I understand what you are doing now. Due to
this special case, the code will dump out the empty trace buffer if
used before anything has been traced (trace_idx=0).
>>> + monitor_printf(mon, "Event %ld : %ld %ld %ld %ld %ld\n",
>>> + trace_buf[i].event, trace_buf[i].x1,
>>> trace_buf[i].x2,
>>> + trace_buf[i].x3, trace_buf[i].x4,
>>> trace_buf[i].x5);
>>
>> Getting only numeric output is the limitation of a binary trace. It
>> would probably be possible to pretty-print without much additional code
>> by using the format strings from the trace-events file.
>>
>> I think the numeric dump is good for now though. Hex is more compact
>> than decimal and would make pointers easier to spot. Want to change
>> this?
>>
>
> I agree, but we can let this be a todo till after the first prototype goes
> upstream ?
I still vote for hex instead of decimal :). Since you're already
spinning a new patch it would be nice to put that change in, but no
worries.
> I'll post patches by Monday that addresses your suggestions, and try to get
> it integrated with QMP.
Excellent, thanks. I'd like to put your patches onto my tracing
branch soon and test out the overall workflow of tracing QEMU.
Stefan
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